Sand and Sun
by Omoni
Summary: I know, I know, this premise has been done a million times. Just let me have my million and one, okay? The world needs more Undyne/Alphys love, dammit. This is the PACIFIST TIMELINE (aka Frisk's playthrough) and contains all the spoilers. So please play the game first before reading this! Part 1 of my "Abovetale" series.


Writer's Note: I suppose this is my way to make up for my first Undertale fanfic ever being a mass word-pile of depression and woe – a fluffy Alphys/Undyne story from Frisk's timeline following the True Pacifist ending. And yes, I'm well aware that although I didn't look, it's quite obvious that likely, by now, HUNDREDS of people have written some version of this story. But I don't care, because I like to write fluff, so just consider this my version and take it just as lightly.

 **Again: SPOILERS FOR THE ENTIRE GAME, INCLUDING THE ENTIRE PACIFIST TIMELINE. So play the game first please! More than once! And how! :D!**

 **Sand and Sun**

It probably could have gone much worse. In fact, she had planned for it to. She had spent hours at the screen, typing line after line of details of the myriad ways in which this supposedly simple idea could go horribly wrong. Even the reasons had reasons added to them. It was a horrible prospect, one that seemed to guarantee failure.

"I'm gonna hurl," Undyne announced when Alphys had shown her the data. Taking her seriously as always, Alphys hurriedly leapt to her feet and tried to steer Undyne away from the computer, as well as try to comfort her with an awkward pat on the shoulder.

"What the…?" Undyne squirmed away, slipping past Alphys and going right back to the computer, no longer looking quite as green around the gills. She pointed at one of the lines, her eye twitching as she read it. Alphys followed her finger and saw, with horror, that the line not only said what Undyne thought it said, but that it was in a different font and colour than the rest of the data.

Flushing bright red, Alphys tried to squeeze past her, muttering, "Damn it, sans…!" She reached over and managed to highlight and delete the line before Undyne could stop her, though she still was pointing and twitching. Of course it would be today that sans would decide to play one of his many random text-attacks. This happened more often than she cared to admit, that somehow, through hacking or some kind of ability she never knew existed but wish it never did, sans managed to write lines like this nestled within her hard work, often too late for her to correct it in time.

Undyne glared at the screen. "Did that really say what I think it said, Alphys?"

"Er." Alphys considered. Which was worse? Admitting she had a sans-problem, or taking blame for the results of that problem?

Undyne's eye suddenly flicked over to her, before a wide grin spread on her face, sending Alphys into a wave of sweat and hand-wringing. "Well?" she pressed, now.

"Drink names?!" Alphys blurted out, remembering that once she had read just that same line in one of her manga, and that it really was the name of a human alcoholic drink. "Er, the other day, sans and I were thinking about… human drink names… and I guess he entered it in the wrong document?"

Undyne raised her eyebrows, still smirking. It wasn't a complete lie, but Alphys knew she was busted. And why was she smirking, anyway? Wasn't she offended? Alphys felt offended.

Mostly.

Quickly, Alphys jumped forward, waving her hands before her in hopes of distracting Undyne away from this horribly sweaty topic and onto another less sweaty one. "But look, look!" She waved her hands at the screen. "I've come up with so many problems with this plan. You may want to reconsider it because, well…"

"If you call one of my plans bad, I will throw you upstairs," was the icy reply. Since she had proven able to do this already on more than one occasion, Alphys took it to heart and shut right up. Undyne went on, her eye back on the screen and her face drawn in annoyance. "Ugh. Alphys… These reasons… What the hell is that one?"

Alphys looked to where she pointed, then moved to try and block the view, fearing it was yet another one of sans's rudely inserted lines. Luckily, or perhaps unluckily, this wasn't the case. The line Undyne pointed to was one in bold and underlined twice: "Beaches are always full of people, who love to make fun of others for not meeting their ridiculous social standards that have never reflected the cultural norm and never will."

"Well… it's true," Alphys said weakly.

"Does Frisk know you made this stupid list?" Undyne wondered, scrolling down the list and scowling even harder the more she read.

"Er." Again Alphys wondered: which was worse? "Well, when you brought this up, I decided to call and ask for some advice, and I kept bringing up a lot of these points. I think maybe I called too many times, because the last time Frisk picked up, they told me to make a pro-con list and, once I was done, send it to them and _then_ call again."

"But this list, Frisk hasn't seen yet?"

"Well, no, not yet. I haven't even started the pro-list yet. The con list keeps getting bigger, and when I think I have something to add to the pro list, it ends up being a con in disguise, so it defeats the purpose of—," Alphys trailed off, suddenly aware of what Undyne was doing to her data.

"Good," Undyne concluded once Alphys was done speaking, making the scientist wonder if Undyne even heard what she said after "not yet". This was made even more true when Undyne, with a wild grin, promptly highlighted the entire wall of text and deleted it with a single keystroke.

Alphys make a noise like she did when someone stepped on her tail, lunging forward to stop Undyne and moving to recover the file. Undyne, however, merely moved closer and stood in a way that made passing her impossible. It was like trying to move a block of concrete.

As Undyne saved the file blank, Alphys was now stammering protests, trying to squeeze past Undyne somehow in order to rectify the damage, if only partially. Undyne merely chuckled at this, her fingers moving over the keyboard much faster than Alphys had ever seen them. But then, Undyne played the piano; of course she had deft fingers.

By the time Undyne moved past, the damage was done. Alphys was amazed at how thoroughly Undyne had deleted her hard work. In fact, she was so amazed that she suspected the worst of this, that Undyne had been taught to do that for this very purpose and by the very same person who enjoyed sneaking embarrassing sentences into non-embarrassing data.

The name brought a long, loud sigh from Alphys, and when Undyne laughed in reply, she knew she was right.

"That had been hours of work, Undyne," Alphys said tersely. She hated talking to Undyne that way, but her integrity as a scientist forbade her to keep silent about it.

Undyne patted Alphys gently on the shoulder, a gesture that was actually quite effective, though she was still annoyed. " _Hours_ , Undyne," she repeated, unable to keep from frowning.

"I know, and I'm kinda sorry," was her reply. She put her hands on her hips, then turned and leaned down, moving to match her height to Alphys's rather lacking height. The result was the inevitable: she forgot how to form complete sentences or how to breathe properly. Undyne this close was like being too close to fire: you wanted to touch it because it was so warm, but you knew one wrong move would get you burnt. That always happened around Undyne.

"Alphy."

The nickname instantly calmed the stammering, forcing the owner of the name into a damp, shy silence, and a small, shy smile. Undyne grinned wider, only the smile wasn't just jovial now: it held a degree of sharpness.

"Y-yes, Undyne?" Alphys replied, already dreading the answer.

"We. Are going. To the beach. Whether you like it or not."

"Er…?!"

And on that, the former Royal Guard grabbed the scientist by the wrist and dragged her away from the screen and upstairs.

* * *

"Mmhm. Okay. So then, it's just like going anywhere else, really, isn't it?"

Alphys stood frozen like a statue, afraid any sudden movement would force her lab coat to somehow open, which she hugged tightly to her body as if for dear life. She stood just behind Undyne, very carefully keeping her eyes glued to the ground and not before her, lest she suddenly dissolve into a puddle as a result. Undyne herself stood as tall and confident as ever, phone to her ear as she listened to Frisk on the other end. Frisk always had to know first before any monster stepped Aboveground, so that they could, if needed, make any preparations for both them and the humans involved easier. This was the norm, one that Frisk promised wouldn't last.

This made Alphys think about Frisk, which was a welcome distraction. Frisk, despite being so small and young, was proving to be incredibly mature for their age, and in the best ways. They seemed to adore every second they spent acting as liaison between humans and monsters. In fact, Alphys had it on good authority that Frisk, without a doubt, seemed born for the role of ambassador. They seemed to thrive best when speaking to both humans and monsters, explaining differences and similarities, how they could learn so much from one another, and the like. They even seemed to love the hard work that came with it. Even when seeming tired enough to fall asleep standing, still Frisk was happy. Alphys didn't really understand Frisk when it came to things like public speaking, especially for inspiration. Lectures she could do, but speeches? She had trouble talking to monsters she had grown up with, let alone a room full of human strangers!

"Yahuh. Like I said, register and-?" Undyne started in mid-sentence, before suddenly blushing, her eye flicking once over to Alphys (who was still staring at her feet, and thus didn't see it) while looking very, very uncomfortable. "Frisk… shut up!" she suddenly growled between her teeth, her eye twitching. ( _Now_ Alphys looked up in interest, as it was rare for Undyne to snap at Frisk that way, at least in such a serious tone.)

"Shh," Undyne hissed, hunching over the phone as if trying to hide it as well as herself. She suddenly started waving her free hand in the air, as if trying to wave away whatever Frisk was saying. "Not a good time, so shut up, kid…" she warned. A pause, and Undyne twitched with her whole body in reply, before stomping her foot a little and growling deep in her throat, her face the brightest red that Alphys had ever seen. It was rather fascinating, and it distracted her eyes away from the rest of her, so it was also useful. "Okay, okay, okay, hahaha, very funny, I got it, okay, bye-bye now, you brat!" and she hung right up, barely finishing her own sentence before doing so.

Alphys blinked again; was that… laughter she had heard on the other end of the phone?

Undyne glared at the phone, panting with her frustration, or perhaps her lack of ability to find some way to get Frisk and a spear to meet through the phone. Slowly, Undyne turned to look at Alphys, who genuinely had no clue what Frisk had said though she very desperately wish she did.

"Er," she said gently, "is everything okay with Frisk?" She didn't want to pry, but she had to ask all the same.

Undyne paused, then said, rather calmly, "Frisk is becoming kind of a smart-ass, huh?"

Alphys considered the question seriously. "I suppose so, yes. Despite how young they are, they do hang around with others much older, so it's inevitable that they would pick up some adult language."

Undyne blinked slowly, then sighed. "That is _not_ what I meant, Alphys," she said, tossing the phone rather aggressively into her shoulder bag before shrugging and standing up straight again. "Whatever." She grinned. "Got everything?"

Alphys, never one to miss out on double-checking anything, promptly checked, blushing the entire time she mentally checked anything off the physical list. Once she had her ID out, her glasses were fogged up.

It wasn't as if this was her first visit to the surface, but it was the first in these circumstances, to be sure.

The first series of visits were not often by choice, though she never regretted any of them. After that first perfect sunset, Alphys had gone up to the surface a few more times to explore, only to be stunned in place by the new world before her. The surface was so much better than anything she had ever seen in human media before. It was as if, though they tried, even humans couldn't accurately depict the beauty of their world. None of what she had seen could have ever truly prepared her for it. She realised as she stared that it was probably impossible for _any_ artist to truly capture it. She certainly tried, and though she had little confidence in much, she took pride in her writing, and even she had fallen through.

When Frisk had been with her during these paused visits, Alphys had asked, "How can you live with such beauty every day and still get any work done?" For some reason, this had earned her a delighted laugh and a hug, though why she still never knew.

Once she managed to find a way to get un-distracted by her surroundings, her Aboveground visits increased, though usually as someone else's "plus-one" on human invitations, which had been the system before the IDs. She usually ended up with either Asgore or Toriel, as Undyne always brought Papyrus (who was never invited personally, like Alphys), and _that_ was because sans _never_ answered his invites, so of course Undyne brought Papyrus along. And while Asgore and Toriel could have gone together, they never did; though Asgore always asked, Toriel always said no.

As she visited more and more, Alphys discovered that she rather liked humans, despite how incredibly different they were from their media. ( _That_ had been a hard lesson learned, having to admit to herself once and for all that yes, anime and manga were not history. She would never tell Undyne this, however.) Many of the humans she met were like Frisk, although she also had to admit that many were very much not like Frisk, at all. But Alphys didn't mind that, as monsters were hardly all perfect, either.

Which suddenly brought Alphys out of her reverie and back to where she was. As a result, she lowered her head and huddled deeper into her lab coat.

"Please don't ask me to check again," she pleaded of Undyne.

Undyne grinned. "Relax. We won't be alone, apparently. Frisk said that both Lesser Dog and Greater Dog are already there. We'll have company!"

Alphys was silent. Though part of her was grateful for the possibility of distraction (as well as added protection from possible – but unlikely – hostile humans), she had to admit to herself that she would have preferred to be alone with Undyne instead.

But only because Alphys was nervous about being out in the open. _Not_ because Undyne made her feel stronger than she was, as if she could be strong enough _for_ Undyne. Of course not.

When Undyne noticed Alphys was still hesitating, she reached own and grabbed her wrist yet again, dragging her forward and toward the way above.

* * *

Again, once on the surface, Alphys stood transfixed. Undyne tried a few times to drag her forward, but she dug her claws in and absolutely refused to move, so she was abandoned. Instead, Undyne walked easily over to the checkpoint and waved to the human there. She came over and chatted with them so easily that Alphys suspected Undyne knew the human already. Leaving her to it, Alphys stood in place, her head tilted back and her gaze on the sky. It was a beautiful day, the sky bright blue and occasionally graced with puffy white clouds.

She heard Undyne and the human laugh, and absently she marvelled at this, admired it, really. When it came to initiation contact with others, unless it took place behind a screen or a wall of text, any attempt usually left Alphys damp and stammering. With Undyne, though, Undyne was always cautious, yes, but she was never afraid.

At first, when the visits began more regularly and more monsters wanted to see the surface, Undyne would always accompany them wearing her full armour. Even when she was invited into the many human-monster meetings, for the first few months, she never took the armour off, no matter what.

Frisk had tried to explain to Undyne that while it was understandable, her wearing the armour constantly was like sending a silent message that she refused to trust anyone.

"I don't," was Undyne's calm reply. She then asked Frisk how they would like to eat one of her spears, only not as nicely or as calmly, which had Frisk scowling but giving up. Undyne continued her stubborn armour-wearing for a while afterwards, but eventually, starting with her helmet, bit by bit, she relaxed enough to eventually not wear it at all. Especially in the summer.

Summers were the best Aboveground, Alphys admitted to herself, watching a cloud skirt by and thinking it looked like a little white dog. When Toriel had successfully opened a school for monsters on the surface, she invited Alphys many times to guest-lecture the older students (which, eventually, would also consist of humans as well as monsters). What was weird was that, in the summer, humans did not go to school; rather, they stayed home, using the time to play and relax.

What was the best thing about summer was actually spent in the Underground. At first, when they learnt that it was the rule for schools to close during the hottest months, Toriel (and later Asgore) would oblige and return to the Underground, Toriel usually returning with Frisk (who always spent their summers with her, as well as pretty much any other chance they could get). This was wonderful in itself for the monsters in the Underground, those too scared or shy to ever leave, as everyone already adored Frisk and would often fight over who spent more time with them next.

However, Alphys loved what came as a result of Frisk's visits. Eventually, a few more human children could be spotted Underground, playing with the monster children as if their own siblings. At first, this caused tension on both sides, as the monsters knew how humans could easily switch from monster-loving to monster-killing, and the humans even thought that the monsters were kidnapping their children. However, once proved to be the exact opposite, and that the children were incredibly well-cared for as well, the Underground became a central hub for summer's children. It was wonderful.

Something jolted Alphys out of this calm reverie quite physically as well as mentally, as suddenly she realised she was moving forward without having any inclination to do so. At one point, Undyne had seized her wrist yet again and was dragging her forward, grinning and waving at the human as they went past. Hurriedly, Alphys held up her ID to the human with an embarrassed smile and a thumbs-up.

The human was laughing long after they were gone.

* * *

Undyne was on the phone again. She was standing just out of earshot of Alphys, one hand on her hip, the other clutching the phone tightly to her ear. She was obviously quite furious, but luckily, instead of trying to eavesdrop, Alphys allowed the beach to distract her, which as actually quite easy.

After a few more checkpoints and a few more odd calls to Undyne (and one text to Alphys from sans: "if you actually swim, i will be disappointed in you, and question your intelligence." She didn't really understand it, but that was pretty normal with sans.), they were finally there, at the beach.

Alphys discovered that beaches were weird. While pleasantly warm and cool all at once, she hadn't expected two major things: one was the water. There was so much of it, seeming to stretch infinitely, and with an entire mind of its own. It was both intimidating and oddly inviting, but Alphys stayed put, too nervous to try this soon.

The second was the sand. She sat on a concrete barrier platform, one that eventually petered out into sand. Her toes were finding the sand quite soothing, the granules slipping over her skin like strange, dry water.

Often, Alphys would journey to Waterfall with Undyne (and, sometimes Papyrus along with them), both of them to run their own errands along the way; Undyne went to keep an eye out for anything hostile, and Alphys used the time to check on her cameras and puzzles.

* * *

One time, when the two of them were alone, and Alphys had just finished replacing one of the camera cables, when suddenly, she felt a seed pod placed gently atop her head. She looked up and saw Undyne grinning, her arms full of them.

"Er," Alphys stammered, "are those… the pods from the puzzle?"

"Yup," Undyne replied happily. She emphasised the point by placing another pod atop the one already on the scientist's head.

Alphys stood carefully still. "Undyne, we need those…"

"Yup," she agreed, placing a third one on the pile.

"…for the puzzle."

"Solved it."

Quite oddly, Alphys felt the seed pods on her head wiggle slightly before twining themselves together. She stayed frozen, not really sure what to do in this situation.

"Er, I suppose that's still accurate?"

Undyne laughed, and suddenly, there was a flash. "Yes."

Alphys reached up and tried to grab Undyne's phone from her hands, all while trying to balance the now-flowers still on her head. "Er…! Undyne! Please tell me you didn't just-?!"

Undyne held her hands up high enough out of Alphys's reach, her fingers flashing over the keypad, still laughing rather happily. Alphys squeaked, and Undyne held the phone down to her. "Here you go. Too late!"

Alphys didn't take it. "You… deleted it, right?"

Undyne merely grinned, her eyebrows quirking amusement.

"Oh."

"You didn't want anyone to see your wonderful hat? Whoops!"

Another time, Undyne made sport of trying different methods of making bridges of the seapods, throwing them as hard as she could in order to see if they would still merge, despite the violence. When they did, Undyne found it delightful, while Alphys decided to install a method of calling the pods back instead of always having to replace them.

The most memorable time, the one that came to focus the most now, was the time they built sand castles. When Undyne was thwarted three times when trying to build flower-towers on Alphys's head, thanks to the bell she installed, she stood scowling at said bell, spear in hand, ready to destroy her destroyer of fun.

"Er…!" Alphys waved her arms and caught her attention. "Please don't!"

Undyne turned to her, her eye sparking. "I want to destroy this. It ruins fun."

"Well, okay, what if we make things for you to destroy that won't compromise the integrity of intricate, complicated puzzles?"

Undyne turned to her completely, interested now. "That sounds fun. What'd you have in mind, Alphy?"

It was the first time she had said the nickname, and for a few moments, Alphys was lost in a wave of sweat and blushing, before wondering if maybe she had misheard it and was getting worked up over nothing. Hastily, to cover it up, she knelt to the ground and started pulling piles of the wet, slick sand together, at first messily and clumsily.

Undyne walked over, spear on her shoulder, wearing a wide grin, though why, Alphys could never guess. She watched Alphys work for a while, and Alphys had to admit that there was something rather enjoyable about this, a mix between channelling her lonely childhood and the pure enjoyment of creating something with just your hands.

She got so into it that by the time she was done, what looked like a slightly lopsided replica of the Core now stood. Alphys grinned, dusting her fingers and leaning back, looking at her work rather affectionately, so much so that she had forgotten the original reason for building it.

"Yesss…!" Undyne crowed, leaping forward and slicing her spear so quickly it was merely a flash of colour before Alphys's eyes. When it was gone, her beautiful sand creation was neatly bisected.

"Er," Alphys murmured, but Undyne wasn't done. With another shout, she proceeded to both kick and punch the remains back into their original form… or maybe even moreso, now.

"Woo!" Undyne threw her arms up in the air and laughed, her smile so wide it seemed to take up most of her face. "That was excellent! Come on, build some more, build some more!"

Surprised and, admittedly, rather entranced by Undyne's passion, Alphys found herself smiling so wide her cheeks hurt. "As long as you don't do that to the real Core, I'll build it as many times as you want."

"Sweet!" And Undyne sat down next to her, watching her eagerly as she worked. They spent the rest of the afternoon doing just that, stopping only when Papyrus called and asked why he was taking his cooking lesson alone.

* * *

This sand, the beach sand, was barely like the sand of the Underground. Though if she dug deep enough, she found sand slightly damp, but nowhere near as clumpy and heavy as the sand she was used to. This sand made her feel oddly primitive; she kept getting mental images of herself curling up in a sand dune and allowing the sun to bake her into a warm ball. Her feet certainly seemed to like the idea, as both were already buried deeply in the sand, and her legs were slowly following. But instead of giving in to this, she merely clutched her lab coat to her and enjoyed the sensation her toes were now having.

Undyne's shouting brought her out of her reverie, as usual, and she looked up to see Undyne storming back towards her, phone still at her ear.

"Shut up, both of you!" she was snarling, her steps so heavy beneath her that she kicked up puffs of sand with every step. "How did you even get this two-voice thing to work?!" She paused, both in speech and in stride, and her face went positively enraged, the answer definitely one she did not like. In response, she threw the phone into the air and had a spear out and ready to slice it.

Greater Dog casually leapt in, grabbed the phone with its mouth, and promptly swallowed it in one go. Undyne and Alphys stared at it, transfixed, as the little soldier seemed to vibrate a little, either from the phone or from pride, before dashing back to its little sandpouf.

"Did-?" Undyne croaked out, spear still out, her eye still on the now-dozing Dog.

"Yes," Alphys agreed sadly. "W-We'll have to wait a while to get it back…"

"Gross," Undyne answered, but a spark of humour sparked within her eye and the spear vanished. Even when Greater Dog started to ring, she merely shrugged. "Really, it's probably best where it is for now."

"Why?" Alphys wondered. As far as she knew, Undyne loved to keep her phone close, always one for sharing random thoughts and observations, especially while on duty, so of course she was curious. Undyne, however, merely glared darkly for a moment, before turning to look at Alphys at last.

"Why? Because Frisk is a smart-ass and Papyrus is not enough of one," was her reply, successfully confusing Alphys into questioning further.

However, when Undyne's gaze focused on Alphys completely, instead of softening, her scowl deepened. "Alphy."

Alphys's heart raced a bit again, like it did every time the nickname was spoken. However, when her eyes met Undyne's, she suddenly decided that perhaps burying herself in the sand was the only solution to this problem.

"Why. Are you still. Wearing that?"

Alphys huddled into her lab coat a bit more, so that her face was partially obscured by the collar, hoping this was a good enough answer. She would do pretty much anything and everything that Undyne asked of her, or so she thought. Apparently today she had discovered a limit.

She certainly didn't need to wear the coat. The day was hot Aboveground and the moment they had walked into the sun she had begun sweating, but still kept the coat on anyway. It was the only protection she had, and not from sun and heat.

"Hm," Undyne crossed her arms and raised one eyebrow. "Maybe I need to go back and get my armour?"

Alphys popped out of her coat to protest at once. "N-no! You can't wear armour here, especially in this heat! You'll dry out, and the sand would damage the joints between the…." When Undyne's face split into a wide, triumphant grin, she suddenly realised she had walked right into that trap, and apparently rather predictably, too.

"Er," was all she could say to that.

Undyne leaned back, standing her full and formidable height, still smiling. As a result, Alphys had to look up to even see her face, though admittedly, at the moment, it was rather… difficult... to focus on just her face…

Alphys coughed. "Er… U-Undyne…"

Her mouth pursed a bit, but the grin remained, her eye sparking. "Yes, Doctor?"

 _That_ was never a good sign. Use of her title meant that Undyne was not just irritated, but enough that she didn't even want to use her name. Alphys looked back down, feeling her glasses instantly fog up in response. "Well, i-it's just…" And now that she couldn't see, it was a little easier to focus, but she still couldn't find the right words.

"Mmhm?" Undyne pressed once Alphys lapsed into silence. Trailing off, a common thing that Alphys used in order to either end a conversation or change focus away from herself, never worked on Undyne, ever.

Without thinking, Alphys took her glasses off and reached down, grabbing the hem of her coat to clean them at least a little. From the corner of her blurry gaze, she caught a flash of a grin, and, before she could even take a breath, she was on her feet and spinning, thrown instantly off-kilter. Once she stopped spinning, she stood frozen in shock, her hand still holding her glasses, the other now empty. She suddenly felt very light, very cool, and very, very exposed.

Somehow, Undyne had taken the coat off in one flick of the wrist and a lift of an arm, as if Alphys was the dinner on top of a table and her coat the tablecloth beneath.

She was silent in her shock for a moment, feeling every drop of blood go straight to her face, her hands still in front of her. "H-how did you do that?" Alphys wondered.

Undyne casually emptied the pockets of the coat, placed what she found (phone, glasses case, ID, and spare notepad and pen) in her shoulder bag, and shook the coat out like a flag. She was grinning so wide her eye was a crescent. Alphys carefully replaced her glasses and looked over at her, wondering if it would be worth it to even try to walk back to get the coat, or to just stay standing where she was, because the damage was done anyway.

Both Dogs were watching them now, Greater Dog occasionally burping out rings. It did nothing to distract Undyne away from her goal.

She was still holding the coat up when Alphys tried, rather quietly, to ask, "M-may I please have that b-back, now, please?" Even though she could already see the answer on Undyne's face, she still felt the need to ask, anyway.

Undyne, in reply, tossed the coat into the air and, with another flash of bright blue, skewered the coat so many times that it looked like a lace doily when she was done.

"Nope," was her cheerful reply.

Alphys made a noise she didn't know she could make, a mix between the sound she made when stepped on and the sound she made when something she worked on still made no sense, a sort of half-whine, half-yell of dismay.

Undyne let the coat drop from her hand, and instantly, Lesser Dog leapt forward and grabbed it in its teeth. When Alphys turned to try and grab it, the Dog took off the opposite direction, the tattered edges of her coat streaming behind like ribbons.

"Damn," Alphys whispered, watching the Dog get smaller and smaller. There was really nothing else to say in this kind of situation.

Undyne looked absolutely delighted. "I'll say," she replied, so casually it instantly confused Alphys, and she looked over. Undyne was wearing the oddest expression on her face, and she was staring at Alphys in a manner that could only be called… leering. Alphys stared back, wondering if her glasses were still foggy or she was misjudging what Undyne was actually looking at.

But when she met Undyne's gaze, and her smile widened even more, she understood completely, and quite suddenly, she couldn't breathe. She stared at Undyne, who stared back. Alphys felt like her whole body was on fire, and it did seem like even Undyne was blushing, just a bit, though her grin hid most of it.

* * *

The reason for this was quite obvious, and it was the same reason why eye-contact with Undyne was rather difficult at the moment. In fact, it was the number-one item on the now-vanished con-list: "Must wear 'swim- or bathing-suits'. _**NONONONONO!**_ "

Undyne, however, hadn't hesitated. In fact, when Alphys had to shy explain it to her, something distant in her eye seemed to light up, and without another word, she grabbed Alphys's wrist and dragged her into Snowdin.

What was stranger? The fact that Snowdin sold suits, or that business was booming? The only store in the entire Underground that carried them was a new shop near the ice dispensary, and it had opened once humans started asking for them. The trend boomed for monsters more than they did the humans, as monsters soon found that, unlike the humans, the temperature of the waters didn't mean as much to them, and thus they could swim all they wanted without the same worries.

Once they both arrived, Alphys was amazed to see that the place was actually rather busy. She was even more amazed when Undyne pushed past everyone in her way, still dragging Alphys behind her, and seemed to know how to navigate the store.

"Uh…" Undyne had said, when Alphys asked her about it. She looked away a bit and said, "Came in with Papyrus a while ago!" while scratching her cheek – all signs of either a lie, or a half-truth. This was made even more obvious when the store clerk not only recognised her, greeting her by name, but also seemed to have something ready for her. He led Undyne (and by extension, Alphys) to the back desk and brought out a big box with her name on it.

Undyne took it, gave him the payment, and then punched him. It wasn't a hard punch, and the clerk seemed absolutely thrilled by it, but it still shocked Alphys anyway. Undyne then stormed out of the store, one hand holding the box, the other, Alphys.

Once back in Hotland, Alphys fidgeted as Undyne opened the box, now looking rather pleased. Undyne didn't used to spend as much time with Alphys in Hotland, but ever since she had found a new place in Waterfall to live, and since that place was much closer to Hotland's border than before, she seemed to find any excuse to visit Alphys, despite the heat. When asked, Undyne cited that the new place had better acoustics for her piano, but Alphys decided to allow herself to pretend that it was actually to be closer to Alphys.

Undyne was holding up something bright yellow, and her eye shone with excitement, her smile so wide it was really amazing to see. "Shut up. Of course we must," she replied cheerfully. Now that she was on familiar ground, she seemed one note away from singing. She reached into the box and pulled another suit from it, this one still wrapped in tissue. "Put this on and don't ask, got it?"

"Asking me not to ask simply means I will make a point to ask."

"Not if you just do it, Alphy."

At that, Alphys took the suit gingerly, hesitating. Then, holding it to her chest, she blushed deeply and, catching Undyne off-guard, managed to slip past her and down the stairs before Undyne was even on her feet to stop her.

By the time Undyne had caught up to her, she was already safely locked in the fake washroom.

" _HEY!"_ Undyne shouted. It sounded like she both kicked and punched the door at once. "You can't fool me, Alphys! I know what's behind that door!"

Alphys scowled at the door, her grip on the suit tightening enough to make the tissue crinkle in protest. Though eventually she did outfit it into an actual working bathroom, complete with sink, counter, and toilet, there was no denying the fact that it still served as a decoy for the real lab. When Frisk discovered her secrets, they had encouraged her to just tell Undyne the truth, if not everyone. When she, as Frisk put it, "chickened out," they told Undyne themself. It was better this way, that Undyne knew, but Alphys wished there had been a better method to it, all the same.

"Come out, now!"

"No. And if you try to come in, I…" she paused, then found herself smirking. "I-I won't go!"

Silence. Then, a very icy voice responded with, "Yes, you will."

"N-no I won't!" Alphys stood still, placing the suit on the countertop and crossing her arms over her chest stubbornly. "Humans… humans have et-etiquette just like we do!"

"Who cares? Get out!"

"If I went to the beach not wearing a suit, it would be exactly like if a monster's child didn't wear striped shirts."

Another silence, so long that Alphys thought for a moment that she had actually won. Until, between obviously clenched teeth, Undyne said, "You put that suit on in there, or I will break in, drag you out, and put it on you myself."

Alphys was suddenly completely senseless, her brain consumed by the haze of pure romance that these seemingly furious words brought up within her. Unhelpfully, her brain supplied her with over a dozen different scenarios as to how this would actually happen, as well as several other variations that usually ended the same way. She was now dizzy and excited with it, her glasses fogged and her hands shaking.

"Er," she said helpfully.

Undyne was silent again. Then she said, "Hold on a second." Alphys did, and she heard Undyne suddenly stomp away from the doorway, which, she had to admit, was a little disappointing.

Until she heard, very muffled, Undyne trying to explain the very situation they were both in over the phone. Alphys lunged for the door, her claws scrabbling at the lock so frantically that she succeeded not in opening it, but jamming it. Of course.

The reason for her panic was obvious: Undyne was sharing this horribly embarrassing mess with someone else, either Papyrus (which she could live with) or Frisk (which she could not). As she listened, still trying to claw the door open, it became obvious that it was indeed Frisk on the other line. It made sense; Frisk did love puzzles and problem solving…

"No. That's just stupid. You heard what I said, right? Or are your ears full of stupid?" Undyne was growling. A pause. "It won't work. It won't. Do you have any idea just how hard it was to even get this far?!" A longer pause, before the sound of Undyne punching something made Alphys scrabble at the door again.

"Who the hell taught you to talk like that?!" Undyne shouted. Then, "Hey! No fair, kid, I'm so much older than you, I've earned my right to use it!"

Another long silence, one so long that Alphys broke into a worried sweat, wringing her hands before her.

Then, finally, "Whatever, whatever. Fine." Undyne growled. "Yes. Yes. Yeah. Yeah. You done? Shut up, then. Yes, you." A pause. "Yes! You're still a little punk!"

Then, to Alphys's abject horror: "Ohhh, really? There's a back entrance, is there? I had no idea. Where?"

"Uhm!" Alphys cried as loud as she could, knocking on the door. "No there isn't!"

Sounding far more cheerful than before, Undyne concluded the call with, "Hey, thanks, kiddo. See ya."

"There isn't!" Alphys insisted, hearing Undyne walk past the door.

"Oh? Then come out with the suit on and let's go!" Undyne instantly replied back.

"Er," Alphys smiled a little, more like a grimace, really. "About that. I apparently…. Jammed the lock. Trying to come out."

"Are you serious, Alphys?"

"I wish I weren't," she admitted honestly.

"Alphys…. I _swear_ …."

"I know, give me a second!" Alphys sighed, hesitating damply, before shooting herself a sour glare in the mirror before she shrugged the lab coat off and unwrapped the tissue. She held it up and eyed it closely, noticing that the suit was actually rather well-made, perfectly tailored for a monster like her. It even looked a little cute, though there was something about it that made her… sweatier than usual. Still, she put it on hurriedly, sparing another fearful look at herself in the mirror before refusing to look any further. Once the suit was on, she grabbed her coat from the floor and shrugged it back on.

Apparently she was taking too long. "Open," Undyne commanded shortly, before proceeding to knock the only way she knew how: by punching the door. Alphys jumped back from the door in surprise, but then she heard a sudden click in the door.

The final knock was rewarded with Alphys finally opening the door, the violence of Undyne's knocking loosening the jam. Undyne still held her fist up when the door opened, and Alphys jumped out and waved shyly. "Uh, hi! I'm here, now!"

Undyne glared at her. "No lab coat!"

"Er, but…" She shifted her weight from one foot to the other, looking up to her… only to suddenly lose her brain. Because her gaze finally took in what Undyne was wearing. She was wearing a bathing suit, yes, and it was the yellow one she had smiled at before, but it was in two pieces, something Alphys didn't realise actually existed outside of anime.

She stared, her mouth dry and her whole body hot. Undyne noticed, and she grinned, posing a little before her, not helping the situation at all. "It's nice, right? Really shows off my muscles, doesn't it?"

And she flexed, proving this to be incredibly true.

When she turned back to Alphys, she was still grinning, until her eye met Alphys's eyes, who was still immobile. Her smile twitched a bit, and she blushed, looking away and scratching her cheek. "Uh… I chose the colours. Do… do you like them?"

"Buh," was all Alphys could utter. When she realised it, she covered her mouth with her hands, utterly mortified. Because not only was her response ridiculous, she suddenly realised why the colour of her suit made her sweaty: it was as close to Undyne's skin tone as a fabric could possibly be. And Undyne's was… yellow. Like…

Alphys bit her lip to keep from making any other noises, her eyes so wide it hurt.

Undyne, however, was grinning again. "Good!" she said, reaching back to smooth her ponytail, a casual enough gesture, except that her fingers seemed to tremble just a bit. Alphys blinked, lowering her hands. Was Undyne… actually nervous?

Could Undyne ever be nervous about something?

"Take the coat off, damn it."

That brought her back. She shook her head and clutched it closed even more. "Er, if it's okay with you, I'd rather—,"

"It's not."

"Er."

"Whatever," Undyne rolled her eye, then grinned, practically beaming. "This is gonna be a good day."

* * *

Now, Undyne said, "I was right, but that's pretty normal. You look—,"

 _"Horrible!"_ Alphys blurted out, covering her face with her hands and cowering a bit. If she couldn't see anyone then she could pretend no one could see her. Especially looking like this.

For a moment, there was a lull between them. Alphys kept hiding, too afraid to look. Maybe Undyne was now realising her mistake and was trying to think of a way to either fix it. Or maybe she was thinking about running away back to the Underground, as far away from Alphys as possible.

The suit itself was a very well-cut one piece, made for a monster with a tail. As Alphys's body tended toward either being too round or too pointy all at once, she had been surprised that it not only had fit, but had actually ended up being rather comfortable. However, despite that, she still felt as if all it did was call attention to the physical flaws she had to face every day, for everyone else to see.

And all in front of Undyne, who looked like a beautiful water-warrior in hers, as if it had been painted on her since birth. Undyne, the one person in the entire world that she wished she could share everything with, was now likely regretting even meeting Alphys.

Suddenly, Alphys realised she was airborne. In retrospect, this wasn't unusual around Undyne, as she tended to do this with many, many people – the more affection she felt, the more force she used. Case-in-point: Alphys landed against the ground, in a soft sand-pile. The hit was jarring, and she was winded from the force of the impact, but she wasn't hurt. That was another thing: though Undyne used all she had, she also seemed to also find a way to make sure the person on the other end didn't get hurt – or at least hurt badly. That was something that mystified Alphys long into the wee hours of the morning.

She lay there, trying to get her breath back, little dots dancing along her vision. After a while, she gave up and shut them again, pretending she was buried deep in the sand and thus invisible. No such luck. She heard Undyne stroll over, and again she was lifted off her feet. However, instead of being thrown, she was placed back onto her feet, almost gently. When she opened her eyes, she saw that Undyne had resumed her seat on the wall and looked absolutely thrilled with herself.

Not really knowing what else to do, Alphys carefully tiptoed to the other side of the wall, giving Undyne what she felt was a reasonable amount of space. She settled onto the seat, no longer bothering to try and hide it. Instead, she merely curled forward and sighed, her glasses instantly fogging up as a result. It was just as well, as she was far too afraid to look over at Undyne, anyway.

A funny thing, that: if she had been able to see Undyne, she would have not only relaxed, but also been given a warning for what was about to come.

"You know something, Alphy?" Undyne's voice was soft, oddly, a tone Alphys wasn't sure she had heard before.

"Probably not, Undyne," she answered miserably.

A pause. Then, she heard Undyne sigh in what sounded like defeat. "Clearly not. I mean, I thought I was being pretty obvious, you know? For someone so smart, when it comes to things like emotions, you're kind of… a dummy, huh?"

Alphys was silent. Hiden behind her glasses, she felt calmer, but Undyne's words made her feel worse. What was she getting wrong? What was she missing? It wasn't like her to miss something…

"Hm…" Undyne drew the sound out long enough to make it seem like its own sentence. Alphys again said nothing, unable to keep from fidgeting with her claws. Her toes were sliding back into the sand, and it was a soothing distraction, despite how terrible she felt emotionally.

If she were to be honest with herself, she did feel much better now without the coat. The heat was nowhere near as smothering, now, and she could even feel the cool, moist breeze of the water, almost as if she could feel the water on her skin without even swimming. It was really, really nice.

She liked the beach.

"Undyne…?" she murmured. "You… you were right."

"Usually," she agreed cheerfully. Was it her imagination, or did she sound… closer? "But what about, this time?"

"The beach. C-coming here was… a good idea." Alphys swallowed hard, then just blurted it out. "Especially… since I'm with you."

Silence. Alphys felt incredibly stupid, now. Had she said something wrong? It was true, but what if it was still wrong? Why wasn't Undyne saying anything?

"Er," she concluded. Her fingers reaching for her phone, before remembering it was in Undyne's bag. She reached for it, found it, and fumbled with it, desperate to do something distracting. (She had ended up typing an entire wall of nonsense letters garbled together and sending it as a text to sans. Long after, sans replied back with "this is awesome. can you use this for the next bulletin?" Along with another similar wall of nonsense text, with a final request: "add this one, too. it's hilarious!")

Suddenly, she felt a cool, scaly hand touch her shoulder, lightly at first, then quite strong. Alphys froze, bracing for another toss, holding the phone close, just in case.

Instead, Undyne leaned close and kissed her on the cheek, the kiss lingering just a bit, before she pulled away, giving her shoulder a gentle squeeze before letting go.

Without any control, Alphys felt her entire body go hot, and she knew she had just done what she hated the most: a full-body blush.

With it, the final line of numbers added up, and she realised that Undyne was right: she was the stupidest person she knew.

"Oh," was all she could say, her voice raspy with shyness. She didn't know it, but she was grinning, the widest grin she had ever managed to make, though her heart was beating so fast, she wondered if she would pass out.

"Yeah. 'Oh.' You big _NERD!_ " Undyne snorted, before being unable to keep it in, and she burst into laughter, normal at first, then full blown-cackling, on and on, the sound made of pure delight. With every laugh, she needlessly punched the ledge beneath her, causing bits of rock to fall off.

At first, Alphys was worried, afraid that this was an overreaction and that they would get into trouble. However, the thought lasted barely a second, before she felt her own laughter bubbling up from within. If you thought about it, Alphys owed Undyne the right to some property damaged.

And that laughter alone was worth every single drop of sweat.

In between peals of it, Undyne gasped out, "For god's sake, Alphy! Aren't you a doctor?! You're supposed to be smart!"

When she dissolved back into laughter once more, Alphys found herself looking over at her, still smiling, her laughs still within her, threatening to erupt. Undyne was laughing so hard she was crying. She looked so happy, so proud, and so incredibly beautiful in that silly moment that Alphys found herself in the midst of an idea, one that worked only the weirdest of fantasies, but…

….well, this was better than fantasy, really.

So, she sat up, leaned over, and, in the middle of a loud bout of chuckles, Alphys darted forward and gave her a hurried, very brief kiss on Undyne's cheek. She immediately felt faint, even when she pulled away, especially when Undyne fell silent and turned to her, her eye wide. Alphys stared back, her heart racing and her hands shaking.

She was afraid of what would happen next. Would Undyne realise her mistake? Would Alphys have to apologise? Had she misunderstood again?

It wasn't an issue. With a flash of a grin, Undyne suddenly shouted, "Sand-wrestling!" and tackled poor Alphys backwards and into the sandy ground. She promptly earned a mouthful of sand and a laughing former royal guard on her, but she couldn't be happier.

Undyne threw her arms around her, hugging her so tightly it hurt, and suddenly, those giggles erupted free, surprising both of them. With a shout of triumph, Undyne leapt to her feet and dragged Alphys to hers, and instead of being tossed, Alphys found herself being embraced. Shakily, she hugged back, trying to stop her own laughs but finding it impossible, now, and the two stood that way, laughing for no apparent reason, covered in sand but feeling not a grain of it.

Then, when both of them had managed to calm down, Undyne gently dropped Alphys back down to her feet, pulled back, and placed her hands on Alphys's shoulders, in that same firm grip. She leaned forward, and Alphys stared, speechless. Undyne looked… unsure, almost as if she were worried.

When she blushed, Alphys felt her own cheeks follow suit. She couldn't help it. "So, uh…" Undyne said, her eye darting to the side as she spoke. "We're... on the same page, right?" She looked back, and swallowed hard, again surprising Alphys. "I mean… we are, right?"

Alphys nodded so hard she went a little dizzy. Before Undyne could even react, however, she reached forward with both hands, reaching for Undyne—

-in order to promptly push her backwards into the sand.

Undyne had only fallen due to surprise, but once she landed, she looked as if she had just been ambushed. She looked amazed at the fact that she was now on the ground. "Huh," she said. "That's never happened before."

And she laughed, stretching out and proceeding to make sand-versions of snowbirds. Alphys laughed a little at seeing this, the activity so silly it was impossible to keep from laughing. Undyne, however, didn't seem to agree, because once she noticed, she reached out, grabbed onto one of Alphys's ankles, and promptly shoved her feet out from under her.

Alphys was shocked, now. She lay on her back, again winded, before she turned to Undyne in confusion.

Undyne suddenly glared. "That was for assuming the worst about yourself. And for insulting my taste. I have excellent taste in people! Don't make me a liar by stripping it to pieces in public with your own groundless doubt."

" _You_ were the one that was stripping _me_ in public, Undyne."

Undyne scowled at her, and Alphys smiled a bit. Undyne flicked a bit of sand at her before pushing herself up to sit up, now completely covered in sand. Alphys smiled, but stayed where she was, quite content, now.

"I'm starting to figure out why Frisk is such a smart-ass," Undyne grumbled, brushing the sand from her hair. However, she smiled, causing Alphys to blush yet again. She wondered if there was anything Undyne could do that _wouldn't_ make her blush.

For a moment, they stared at each other, Undyne with affection, Alphys with barely-restrained adoration.

"Did sans really write that, before?" Undyne suddenly asked, one hand slowly sliding through the sand towards Alphys.

However, at the question, Alphys jumped and sat up. "Y-yes! Of course! I promise!"

When Undyne pouted, Alphys was yet again speechless. "Huh, well… it wasn't the worst idea, really. The name of that drink."

"Uhm!" Alphys squeaked out, nearly falling over again. She wondered if the beach's air was capable of making someone drunk. Was Undyne drunk? Was _she_?

"I'm joking! I'm joking, Alphy. Sheesh."

Alphys relaxed.

"Mostly."

That hadn't lasted long.

A pause.

"The Dogs are nosy. They would just watch everything and then tell everyone."

Alphys slapped her hands to her mouth, barely able to believe something like that had just come from it. Undyne raised her eyebrows at her, looking about to choke on her laughter.

"Oh, really, now?" she replied, leaning towards Alphys ever-so-slightly, so close that Alphys wondered if it were possible to blush to death. She looked down, unsure of what to say or what to do. Though Undyne was teasing, Alphys wondered if she still had done something wrong.

She needn't have worried, really.

"So, what you're saying is, if the Dogs weren't here…"

Alphys looked up at her, having no idea where she was going with this.

"…you'd want to try that human drink?"

When Alphys did fall over and try to bury herself into the sand, Undyne laughed so hard she both cried and almost puked.

Alphys definitely liked beaches.

* * *

Postscript: Yes, sans wrote "Sex on the Beach."


End file.
